Development of a Fuzzy Model for Predicting Load Constant and RWL in Manual Material Handling Tasks for Indian Industry Workers

Human centred system (HCS) is understood as the system of Human-Machine-Environment where the people at work have their relations with the surrounding environment, equipment, fellow workers and their work. The analysis of such systems can be performed aiming at different goals such as safety, health, human reliability, stress or usability. This research deals with the evaluation of load constant (LC) during manual material handling (MMH) tasks and then evaluation of recommended weight load (RWL) with temperature effect. Load constant is defined as the load that is lifted by worker without any musculoskeletal problem. There are several kinds of injuries and disabilities associated with manual material handling tasks, among which low back disorders (LBDs) represent the most common and most costly musculoskeletal disorder (MSD) experienced in the workplace. Much of this LBD is associated with occupational factors and significantly increases workers compensation costs. MMH tasks have been associated with the majority of lower back injuries. The value of LC suggested by thenational institute for occupational safety and health (NIOSH), may change with age, height and strength (capacity) of worker. In this research fuzzy logic approach is used for calculating the load constant for each worker in industry. Implemented findings may help improve safety and motivation of workers that can, in the long run, contribute to competitiveness and sustainability of workgroups. Safety of the worker, indirectly will reduce the compensation cost of the worker and finally will help to the industries to sustain in the global marketplace.